Transistors Changed Everything. Here's How They Work

How a tiny little electronic switch sparked the computer revolution. Last week I revealed the sneaky physics behind the " joule thief," an electrical circuit that lets you squeeze more energy out of seemingly dead batteries. The key, it turned out, was a clever pairing of a transformer and a transistor. But the transistor deserves its own headline, because it's maybe only the most important invention of the 20th century. Life would be completely different without transistors.